Early in Magic!’s record release show at West Hollywood’s Troubadour nightclub, frontman Nasri Atweh asks the young, giddy crowd, “You guys like reggae music?” The people cheer, which is no surprise: The next day, the Los Angeles-via-Toronto quartet will drop its debut, Don’t Kill the Magic, a shiny collection of breezy pop tunes often accented by laidback reggae rhythms, especially on song-of-the-summer contender “Rude.”

Magic! have been together less than two years, but the singer — who records under the name Nasri because “I just think it sounds cooler” — has been a radio force for years, collaborating with Adam Messinger to write and produce hits for artists like Pitbull (“Feel This Moment”), Chris Brown (“Don’t Judge Me”) and Justin Bieber (“Never Say Never”). Nasri had always wanted more, though: “When I was six, I knew I was going to be a singer,” he tells Rolling Stone while hanging out at the band’s North Hollywood studio the following afternoon. As with most everything Nasri says, the comment is delivered with a seamless, serene mixture of confidence and humility. Here, he discusses his relationship with Bieber, defends feel-good music and explains why despite making stoner-friendly songs he doesn’t light up.

You’ve had success as a hitmaker-for-hire. Did you fear getting pigeonholed as “the guy who writes for other people”?The industry didn’t want to support [my career]: “Oh, there’s enough stars, but there’s not a lot of good writers.” I said, “I don’t care what you think. I won’t write for you anymore.” I made a solo album right before Magic! — Atlantic Records wanted to sign me, and they said, “You could be a modern-day Seal.” And I was like, “Okay, I’ll try that.” The album sounded good, but I always was kind of bored. My personality, although I’m very relaxed right now, is a little more zany and a little more out-there. When I met [Magic! guitarist] Mark [Pelli], I got pumped. We could do whatever we want — and with reggae, you get to be sensual and fun at the same time. So I really found myself through the band.

Was reggae something you heard growing up?I loved reggae, man. Toronto’s got a pretty heavy reggae scene, and anybody who grows up doing R&B understands reggae: It’s rhythmic, it’s soulful. You’re just born with it. Since I was a kid, if somebody started [mimics a reggae beat], I could flow on it.

When I was young, I thought I was going to be a pop star: “I’ll be in a boy band.” I had spiky hair, I was super-ripped and I was working out two hours a day. I had no musical education, so I thought, “I’ll just pop and lock.” Backstreet Boys were big at the time, but within about a year, I discovered soul music. After that, I didn’t want to do pop music anymore. I stopped caring about being famous — I only cared about being good at music. I would use my playful charm and my will to win — I would paint people’s walls and fix their roofs just to get sessions. I was scrappy, but I was a good writer: It was evident to people around me that I was writing catchy stuff all the time.

You’ve worked with some pretty famous, and divisive, pop stars. Are there things about, say, Chris Brown or Justin Bieber that the rest of us don’t understand just by following their exploits on TMZ?The funny thing is, Chris Brown is just a music lover. He loves making music — he sits in the studio all day. Justin is a lot more like me: What he likes is more soulful, and his personality is out-there. I spent probably the most time with Justin out of everyone, because I did a lot of Justin’s records. I look at him like a little brother.

With his recent personal problems, have you reached out to him like an older brother would?I just text him: “Are you cool?” He’s like, “Yeah, I’m cool.” It’s none of my business. He’s a grown man.

Still, making music with someone is an intimate thing.It is, but it’s work. I could have written something else that day, but I was working for him. He knows that if he wants to escape, he can escape to certain creative people. You do what you gotta do. I mean, it’s funny: Justin just called me the other day to congratulate me on “Rude.” And I’m like, “Yeah, let’s work. Let’s do some things.”

At your show, I was impressed you pulled out a cover of Stevie Wonder’s “Master Blaster.”My influences are Stevie Wonder, Michael Jackson, Sting and Bob Marley. I never really take from anybody new — I go to the good, strong songs from back in the day. I like catchy music, but I don’t like corny music. I have that fine line in my head, and “Rude” is right there. “Rude” could easily be corny.

So, what keeps “Rude” from becoming corny?I was careful with the way I was singing to just keep it cool. And the tempo, it’s got some swag to it.

Initially, “Rude” was written about an ex-girlfriend, right?Yeah, it was a rough night, and she was mean. The next day, I was just writing: “Why you gotta be so rude? / Don’t you know I’m human too?” That hook really stuck with Mark more than me — I didn’t care. He kept saying, “You gotta write that song.” I was like, “I don’t like it.” And then I played the hook for Adam one day, and he was like, “You should try it more happy.” He was playing the guitar and I started singing this whole story. Wrote it in about 15 minutes — it just came out. So, yeah, there’s an evolution to the song, but it comes from somewhere real. I think that’s why people feel it.

Some people tend to dismiss songs like “Rude”: If a song just makes you feel good, it doesn’t have depth.Absolute nonsense. To assume that the human race cannot understand [a performer’s] emotion, when everyone is constantly feeling emotion, makes no sense. I never underestimate people; I think people are very intelligent. You just have to have the courage to give it a shot and make something with some soul. Look at Sam Smith: People love him because people have souls.

Reggae comes in and out of popularity…It’s a shtick to people.

Exactly. So how does Magic! avoid shtick?The lyrics. I’m not gonna talk about Rastafarianism — we just talk about love. The reggae part is not a shtick to us as musicians — we do that naturally. And reggae is not for one color or creed — it never was meant for that. We’ve met so many great reggae artists who say, “You’re killing it.” It’s just music. Our album is really only about 70 percent reggae. If the next album’s 50/50, cool — if the next album is a folk album, whatever. It’s more focused on good songs than anything else, because you’re not going to see me with dreads, smoking a joint. I don’t smoke the weed — I’m really just creating vibes.

Did you ever smoke?I drank once when I was, like, 16. I smoked a joint once — not too much, just a little bit — and I thought, “Oh, that’s what it’s like to be high.”

Are you sober because you want to stay focused?No, I’m just lucky: I’m comfortable in my skin.

You realize Magic!’s music is gonna inspire people to light up.Totally. We’ll end up doing festivals, and people will be pretty zonked.